This invention relates to a method of injecting tin-containing antifoulants into thermal cracking (pyrolysis) process streams so as to alleviate the undesirable formation of coke and carbon monoxide during subsequent thermal cracking of light hydrocarbons. In a particular aspect, this invention relates to injecting tin-containing antifoulants into process streams for thermal ethane cracking reactors (to make ethylene).
Numerous tin-containing antifoulant agents for reducing the formation of coke on the metal walls of light hydrocarbon pyrolysis (thermal cracking) reactors are known and have been described in the patent literature, such as U.S. Pat. Nos. 4,404,087, 4,507,196, 4,545,893, 4,551,227, 4,552,643, 4,666,583, 4,687,567, 4,692,234 and 5,015,358. These tin-containing antifoulants (either tin compounds or mixtures of tin and other compounds) can be injected into a hydrocarbon-containing feed for a thermal cracking reactor. The present invention is directed to an improved method of injecting tin-containing antifoulants into thermal hydrocarbon cracking process streams so as to alleviate the deposition of coke on metallic reactor walls and/or the generation of carbon monoxide during the subsequent thermal cracking of these hydrocarbons.